000 AXNT20 KNHC 060515 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 115 AM EDT Fri Apr 6 2018 Tropical Weather Discussion for North America, Central America Gulf of Mexico, Caribbean Sea, northern sections of South America, and Atlantic Ocean to the African coast from the Equator to 32N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0000 UTC surface analysis and satellite imagery through 0445 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the border of Sierra Leone and Guinea on the coast of Africa near 09N13W to 04N17W. The ITCZ continues from 04N17W to 02N22W and then to the coast of Brazil near 01S47W. Scattered moderate and isolated strong convection is present within an area bounded by 06N11W to 04N32W to 02S38W to 02S30W to 06N11W. ...DISCUSSION... GULF OF MEXICO... High pressure centered over the NE Gulf just S of Mobile Alabama near 30N88W ridges southwestward across the Gulf of Mexico to the Bay of Campeche. Coverage of convection over the Gulf has diminished as convergent winds aloft associated with broad mid to upper-level ridging building over the Gulf from the west moves overhead. Moderate to occasionally fresh E to SE winds are causing seas to build to between 4 and 5 ft over the western Gulf. Otherwise, seas are running in the 2 to 4-foot range. Looking ahead, winds will veer from the SE and S across the region Friday through Saturday ahead of the next cold front, which is due to enter the NW Gulf Sat evening. The front will move SE then stall from S Florida to the Bay of Campeche by Sun evening. CARIBBEAN SEA... Tranquil weather prevails across the Caribbean tonight. Mid to upper-level ridging extending northward over the basin from South America is promoting a relatively dry weather pattern. The only exception to this is over Hispaniola, where a weak upper-level trough helped to trigger scattered showers and isolated thunderstorms over the higher terrain during daytime heating on Thursday. The trough is expected to move eastward away from Hispaniola and allow shower coverage to decrease during the next couple of days. The trade winds over the basin remain lighter than normal as low pressure systems continue moving eastward from the United States to weaken the ridge to the north. Consequently, the seas are running fairly low across the area, with the highest seas around 5 ft near the coast of Colombia. No significant changes in the weather pattern is expected during the next couple of days as the ridge to the north remains weak. ATLANTIC OCEAN... A cold front enters the discussion area near 32N64W, then extends southwestward to 26.5N73W, then continues as a weakening cold front to the Straits of Florida near 24N80W. This boundary is weakening and has lost all of its deep convection. Patchy cloudiness and isolated showers are present along and up to 180 nm northwest of this boundary. Two weak surface troughs are located to the east of the front. The first extends from 30N65W to 26.5N68W. The second trough curves southward from 25N69W to 24N71W to 22N70W. No significant convection is currently associated with these troughs. Cloudiness and isolated showers are observed within 150 nm of the axis of another broader trough that is located along 56W from 14N to 22N. Farther east, a weakening cold front is producing a narrow band of clouds and showers along its axis from 32N19W to 29N27W to 28N37W. Otherwise, 1027 mb high pressure centered SW of the Azores near 36N40W dominates the central and eastern Atlantic. Fair weather and moderate trade winds are currently prevail over the tropical Atlantic N of the ITCZ and W of 30W. These winds will become fresh by Sun as the high builds. The next cold front is expected to enter the far western Atlantic waters Saturday night. For additional information please visit http://www.hurricanes.gov/marine $$ McElroy